A wide variety of blister packages for packaging a variety of consumer products are available in the art. These blister packages typically are formed of a transparent layer (the “blister”) coupled (preferably sealed or otherwise bonded) to a backing layer. The blister has a well or cavity or other type of deformation formed therein such that upon coupling of the blister to the backing layer a compartment or pouch is formed for holding or containing a desired product. The product well(s) may be accessed by stripping the backing layer from the package to expose the well and the product therein, or to expose a rupturable/push-through backing layer below the well through which the product may be pushed upon exerting pressure on the blister and the article (a “peel-and-push” blister package). Alternatively, the well(s) may be accessed by tearing the edge of the package toward such well(s) (a “tear-access” blister package). A starting notch or slit may be provided to facilitate tearing.
One common use of blister packages is for packaging solid-dose medications or pharmaceuticals (e.g., tablets, capsules, caplets, and the like; hereinafter “medications” for the sake of convenience and with no intent to limit) or consumer products. Such packaging typically is desirable for carrying individual/unit doses of medication, and may afford a greater level of portability than other types of packaging (e.g., bottles). Like typical blister packages, blister packages for medications generally permit moderately easy viewing of the contents therein. Such easy viewing may tempt a small child to try to access the product. The Consumer Product Safety Commission has established rules governing which products require special packaging and standards for such special packaging in the Poison Prevention Packaging Act of 1970, outlined in the Code of Federal Regulations, Title 16, Part 1700. “Special packaging,” commonly referenced as child-resistant or CR packaging, is defined in 16 C.F.R. §1700.1 (b)(4) as “packaging that is designed or constructed to be significantly difficult for children under 5 years of age to open or obtain a toxic or harmful amount of substance contained therein within a reasonable time and not difficult for normal adults to use properly, but does not mean packaging which all such children cannot open or obtain a toxic or harmful amount within a reasonable time.” Products requiring special packaging include all prescription medications and over-the-counter medications, and a variety of other substances that are harmful if handled, used, or ingested. Child resistant blister packages are also desirable for packaging any other type of article that is unsafe for a child, such as medical instruments, sharp objects, or addictive substances (e.g., caffeine, nicotine, etc.).
A variety of manners of forming a child-resistant blister package are known in the art. For instance, a peel-and-push type blister package generally requires sufficient cognitive skills to render the package child-resistant. Tear-access type blister packages may be formed of a tear-resistant material that is nearly impossible to tear unless the material is weakened (such as by perforations) and a minimum amount of force, generally greater than within the capacity of a child, is used. Child-resistant blister packages must, however, take into account the needs of the adults who are to access its contents. In particular, the child-resistant blister package should be designed to permit senior and physically disabled adults to open the package readily. If the tear resistance of a child-resistant tear-access blister package is reduced for ready opening by a senior or physically disabled adult, then there is a risk that a child may open such package as well.
Additional features (e.g., requiring folding, tearing, or stripping to gain access to the content of the product well) may be required to add a further step beyond the cognitive skills of small children. Thus, a high tear resistance may not be necessary for a tear-access blister package to still qualify as child resistant. For instance, a tear-initiating notch (generally required in tear-resistant blister packages for initiating a tear) may be inaccessible unless the blister card is folded over, such as disclosed in U.S. Pat. Nos. 3,809,220 to Arcudi and 5,511,665 to Dressel et al. Alternatively, a portion of the blister card may have to be removed first in order to permit tearing of the package to access the contents of the blister, as disclosed in U.S. Pat. No. 6,422,391 to Swartz. The requirement of tearing at a particular location on the blister package also elevates the cognitive skills required to open the package, such as requiring initial tearing through a peripheral tearing blister, as disclosed in U.S. Pat. No. 6,036,016 to Arnold. Another added step elevating the cognitive skills required to open the blister package beyond those of a typical child may be to require manipulation of the medication in the blister before rupturing the blister package to access the medication, such as disclosed in U.S. Pat. Nos. 4,371,080 to Haines and 5,529,188 to Coggswell.
There remains a continuing desire in the industry to improve the child-resistant features of tear-access blister packages to improve consumer friendliness and ease of opening for adults, including senior and physically disabled adults.